Special concrete wear-resistant agent for airport dam

Abstract

The invention relates to the technical field of concrete wear-resistant materials, and discloses a special concrete wear-resistant agent for airport dams, which comprises the following components in percentage by weight: 50-70% of siliceous cement and more than 85% of S < O2 >. 10%-20% of natural volcanic rock mineral powder; 3%-5% of nanoscale silicate powder; 2%-4% of nano iron oxide; 2%-3% of zinc-rich mineral powder; 2%-4% of diamond-like carbon coating particles; polyurethane or polyurea, the mixing amount of which is 2%-3%; the wear resistance, the impact resistance, the high temperature resistance and the corrosion resistance of the concrete are remarkably improved. The unique formula can effectively solve the problems of poor wear resistance, easy cracking and insufficient impact resistance of traditional concrete, and is suitable for high-speed water flow, sand washing and high-corrosion environments. The wear-resistant agent has a good application effect, is widely applicable to projects such as water conservancy and hydropower, airports and bridges, and improves the durability and stability of concrete structures.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete wear-resistant materials, and specifically to a special concrete wear-resistant agent for airport dams. Background Art

[0002] With the continuous development of infrastructure projects such as water conservancy and hydropower projects, bridge projects, and airport dams, how to select suitable materials to cope with the impact and wear in high-speed water flow and sand scouring has become an important issue in engineering design. Especially during flood discharge, the particulate matters such as sediment and bed load carried in the water flow will cause serious impact and wear on the surface of hydraulic concrete under the action of high-speed water flow. Factors such as the flow velocity of the water flow, the shape, particle size, and hardness of the sediment particles, and the sediment content of the river channel will directly affect the wear resistance and impact resistance of the concrete.

[0003] In the prior art, the wear resistance of hydraulic concrete usually depends on the strength and surface hardness of the material itself. However, for long-term use under the impact of high-speed water flow and the friction of sediment particles, traditional concrete materials often fail to provide sufficient protection, especially in terms of the balance between surface hardness and toughness. During flood discharge, the water flow generally rubs against the concrete surface at a relatively high flow velocity and with small suspended sediment particles, causing uniform abrasion and peeling. At this time, surface hardness becomes the key factor determining the wear resistance of the concrete, rather than toughness.

[0004] Traditional concrete surface protection materials are mostly mineral additives with single functions. Although they can improve the impact resistance and wear resistance of concrete to a certain extent, when facing high-speed water flow and long-term wear, the performance of these materials degrades rapidly and it is difficult to meet the high requirements for wear resistance and impact resistance in modern water conservancy and hydropower, bridge projects, and airport dams. Therefore, how to enhance the wear resistance, impact resistance, high-temperature resistance, corrosion resistance, and other multi-faceted performances of concrete while increasing its hardness has become the main challenge faced by the current technical solutions. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a special concrete wear-resistant agent for airport dams, which solves the problems of insufficient wear resistance and poor impact resistance of the concrete surface under high-speed water flow and sand scouring.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: The special concrete wear-resistant agent for airport dams, by weight percentage, comprises the following components:

[0007] Siliceous cement 50%-70%, with SiO2 content greater than 85%;

[0008] The silica cement used in the present invention is the core cementitious material of the wear-resistant agent, with an SiO2 content higher than 85%. While ensuring good hydration activity and bonding strength, it provides extremely high chemical stability. Compared with traditional ordinary portland cement, the pozzolanic reaction potential brought by the high SiO2 content is stronger, and it can synergistically react with the nanoscale active substances added subsequently to generate more dense C-S-H gels, thereby reducing the capillary porosity and enhancing the overall erosion resistance. In practical applications, it plays a key supporting role in the structural uniformity and stability of the cement paste;

[0009] 10%-20% of natural volcanic rock powder;

[0010] As an auxiliary cementitious material, volcanic rock powder participates in the mixture in a mass ratio of 10%-20%. It not only enhances the active reaction ability through its natural volcanic glass composition, but also, due to its rough and porous particle structure, can effectively increase the mechanical bite force between the cement paste and the aggregate and improve the performance of the interfacial transition zone (ITZ). More importantly, the reactive silica in the volcanic rock powder undergoes a secondary reaction with the cement hydration products, which helps to fill the micropores in the concrete and improve its durability and crack resistance;

[0011] 3%-5% of nanoscale silicate powder;

[0012] In order to further enhance the strengthening effect of the wear-resistant agent at the microstructural level, the present invention introduces nanoscale silicate powder with a dosage of 3%-5%. This powder has an extremely high specific surface area (up to 60000 cm 2 / g) and nanoscale particle size (50-100 nm), enabling it to be rapidly activated during the early hydration process, acting as a nucleation center, promoting the rapid deposition of C-S-H gels, and significantly accelerating the hardening speed of the paste. Due to the dispersion effect and space filling effect of the nanoparticles, it exhibits obvious micro-filling and densification effects in the cement matrix, effectively inhibiting crack propagation and improving the impermeability and impact resistance;

[0013] 2%-4% of nano iron oxides;

[0014] In the further optimization of the material system, the present invention selects nano iron oxides (Fe3O4 or its composites) with a particle size in the range of 30-50 nm and incorporates them into the system at a ratio of 2%-4%. The mechanism of action of the iron oxides not only lies in their participation as densifying particles in the filling of the cement matrix, but also in their ability to generate a stable protective film on the surface of microcracks through microscopic reactions with hydroxide ions, blocking the further erosion paths of chloride ions and sulfate ions, thereby improving the electrochemical stability of the concrete in complex environments such as salt corrosion and freeze-thaw;

[0015] 2%-3% of zinc-rich ore powder;

[0016] To enhance the durability of concrete in humid and highly corrosive environments, the present invention incorporates 2%-3% of zinc-rich ore powder. Zinc has excellent cathodic protection in an alkaline environment, and its incorporation can significantly inhibit the electrochemical reaction of steel bar corrosion. At the same time, the zinc-rich ore powder reacts slowly with the cement hydration system to form a weakly alkaline zinc salt film on the material surface, effectively delaying the intrusion rate of chloride ions into the concrete structure and providing additional corrosion resistance enhancement to the interfacial bonding zone;

[0017] 2%-4% of diamond-like carbon coated particles;

[0018] Diamond-like carbon coated particles, with their extremely high hardness (close to diamond), excellent wear resistance and chemical inertness, form a high-strength microstructural protection barrier on the concrete surface. These particles are dispersed and embedded in the cement matrix during mixing, significantly improving the surface wear resistance and erosion resistance, especially suitable for environments with high-speed water flow or frequent mechanical abrasion. In addition, their good particle size distribution (50-100μm) ensures good distribution and stable interfacial bonding of the particles in the overall system, without causing microcracks in the material;

[0019] Polyurethane or polyurea, with a dosage of 2%-3%;

[0020] Based on high-performance inorganic materials, the present invention innovatively introduces polyurethane or polyurea-based polymer elastomers into the concrete wear-resistant agent system, with a dosage of 2%-3%. This polymer still has excellent stability in an alkaline environment. Its introduction not only plays a role in internal cohesion enhancement, but also improves the flexible crack resistance and impact absorption capacity of concrete. A good physical cross-linking and chemical interfacial adhesion are formed between polyurethane and inorganic materials, showing the toughness advantage of composite materials under multiple environmental loads, thus effectively avoiding the defect of "strong but brittle" of traditional high-strength concrete;

[0021] 0.5%-1% of modified calcium ion additive;

[0022] In addition, to further optimize the hydration reaction process and early strength growth curve between materials, the present invention adds 0.5%-1% of modified calcium ion additive to the system. The selected modifiers such as calcium aluminate cement, calcium nitrate or calcium chloride all have fast calcium release performance, which can accelerate the reaction process of C3A and C3S in the initial hydration reaction, improve the early strength of the system and enhance the cement bonding force in the interfacial zone. This early strength promotion effect is particularly prominent in winter construction or scenarios with high requirements for early demoulding.

[0023] Among them, the total dosage of the wear-resistant agent is 3%-20% based on the mass of the binder.

[0024] The total dosage of this wear-resistant agent is controlled within the range of 3% - 20% of the mass of the cementitious material. Considering economy and strengthening effect, it can be flexibly adjusted according to the specific engineering requirements. Its dry powder state design is convenient for on-site construction use. It can be directly mixed with cement, sand, and fly ash and put into a mixer to complete dispersion and fusion, avoiding problems such as difficult metering and uneven distribution existing in traditional liquid additives.

[0025] Preferably, the specific surface area of the nano-silicate powder is 60000 cm2 / g, and the particle size range of the nano-silicate powder is 50 - 100 nm.

[0026] Preferably, the particle size range of the nano-iron oxide is 30 - 50 nm, and the nano-iron oxide is Fe3O4 or its composite.

[0027] Preferably, the siliceous cement is selected from special cements with a C2S content greater than 40% and a C4AF content greater than 15%.

[0028] Preferably, the particle size range of the natural volcanic rock powder is 50 - 200 μm, the particle size range of the zinc-rich ore powder is 50 - 100 μm, and the particle size range of the diamond-like carbon coating particles is 50 - 100 μm.

[0029] Preferably, the modified calcium ion additive is selected from calcium aluminate cement, calcium nitrate, or calcium chloride.

[0030] The present invention also provides a preparation method of a wear-resistant agent for airport dams special concrete, comprising the following steps:

[0031] S1. Material preparation: Prepare siliceous cement, natural volcanic rock powder, nano-silicate powder, nano-iron oxide, zinc-rich ore powder, diamond-like carbon coating particles, polyurethane or polyurea, and modified calcium ion additive;

[0032] S2. Premixing of basic components: Put the siliceous cement and the natural volcanic rock powder into a mixing device according to the designed ratio, and stir for 2 - 3 min to form a uniform basic mixing system;

[0033] S3. Addition and mixing of functional materials: Sequentially add the nano-silicate powder, nano-iron oxide, zinc-rich ore powder, and diamond-like carbon coating particles into the basic component mixture, and continue to stir for 5 - 8 min to make the functional nano-materials uniformly dispersed and in full contact with the basic powder materials;

[0034] S4. Incorporation of polymer and additive: Add polyurethane or polyurea polymer materials and the modified calcium ion additive into the above mixing system, and mix again for 3 - 5 min so that all components are uniformly fused to form a high-performance composite wear-resistant agent.

[0035] The present invention further provides the application of a special concrete wear-resistant agent for airport dams. This wear-resistant agent is applied to airport dam concrete or mortar projects with relatively severe erosion and cavitation resistance requirements to improve the erosion resistance strength and cavitation resistance performance of the concrete. The applicable concrete strength grade for this project is C60 to C80.

[0036] Preferably, the wear-resistant agent is added to the concrete mixer simultaneously with cement, fly ash or sand in dry powder form, or added to the dry materials. It is strictly prohibited to mix with water alone or measure by volume method. The feeding sequence is: small stones, sand, cement, fly ash and the wear-resistant agent, and finally water is added. The mixing time is extended by 90 seconds compared with ordinary concrete or the total mixing time is not less than 180 seconds. If it is necessary to shorten the mixing time, it should be confirmed through a mixing uniformity test.

[0037] The present invention provides a special concrete wear-resistant agent for airport dams, which has the following beneficial effects:

[0038] 1. By adopting a composite technical solution of various functional components such as nano-scale silicate powder, nano-iron oxide, and zinc-rich ore powder, the present invention improves the wear resistance and impact resistance of concrete. Through reasonable component ratio and particle size control, the material exhibits excellent anti-damage ability during friction, wear and impact processes. Compared with the simple combination of conventional cement and mineral powder in the prior art, the present invention effectively solves the problems of insufficient wear resistance and cracking under impact, enabling the material to maintain a longer service life in complex environments.

[0039] 2. By introducing polyurethane or polyurea polymer materials, the present invention further enhances the flexibility and crack resistance of the material, especially showing excellent performance in engineering environments with high impact and vibration. The addition of polyurethane enables the material to absorb more energy when stressed, reducing the risk of crack propagation and fracture. Compared with the solution that simply relies on mineral materials for strengthening in the prior art, the present invention has made significant progress in impact resistance, solving the problems of easy cracking and poor impact resistance in traditional solutions.

[0040] 3. The present invention combines a modified calcium ion additive with a special siliceous cement to optimize the high-temperature resistance and corrosion resistance of concrete. In high-temperature and corrosive environments, the material shows good structural stability and low mass loss. Compared with traditional concrete materials, the design lacking calcium ion additives often leads to structural damage and performance degradation of the material under high-temperature or corrosion conditions, while the present invention solves this problem, significantly improving the high-temperature resistance and corrosion resistance, making it suitable for more extreme application environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a flow chart of the preparation method of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0042] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0043] Please refer to the attached Figure 1 , the special concrete wear-resistant agent for airport dams provided in the following embodiments of the present invention.

[0044] Example 1: High wear-resistant airport dam concrete wear-resistant agent

[0045] Components and mass percentages: Siliceous cement 60%; Natural volcanic rock powder 15%; Nano-scale silicate powder 4%; Nano iron oxide (Fe3O4) 3%; Zinc-rich ore powder 2.5%; Diamond-like carbon coating particles 3%; Polyurethane (polyurea) 2.5%; Modified calcium ion additive 0.8%.

[0046] Preparation steps:

[0047] Material preparation: Prepare the required raw materials: 60% siliceous cement, 15% natural volcanic rock powder, 4% nano-scale silicate powder, 3% nano iron oxide, 2.5% zinc-rich ore powder, 3% diamond-like carbon coating particles, 2.5% polyurethane, 0.8% modified calcium ion additive;

[0048] Premixing of basic components: Put 60% of siliceous cement and 15% of natural volcanic rock powder into a mixer in proportion and stir for 2 minutes to ensure uniform mixing;

[0049] Addition and mixing of functional materials: Add 4% nano-scale silicate powder, 3% nano iron oxide, 2.5% zinc-rich ore powder and 3% diamond-like carbon coating particles to the basic mixture in sequence, and continue to stir for 5 minutes to ensure uniform dispersion of the nano materials;

[0050] Incorporation of polymer and additive: Finally, add 2.5% polyurethane and 0.8% modified calcium ion additive, and mix for 3 minutes to ensure complete fusion of each component to obtain the final composite wear-resistant agent.

[0051] Example 2: High erosion-resistant airport dam concrete wear-resistant agent

[0052] Components and mass percentages: Siliceous cement 65%; Natural volcanic rock powder 12%; Nano-scale silicate powder 5%; Nano iron oxide (Fe3O4) 2.5%; Zinc-rich ore powder 3%; Diamond-like carbon coating particles 2.5%; Polyurethane (polyurea) 2%; Modified calcium ion additive 0.5%.

[0053] Preparation steps:

[0054] Material preparation: Prepare the required raw materials: 65% siliceous cement, 12% natural volcanic rock powder, 5% nano-silicate powder, 2.5% nano-iron oxide, 3% zinc-rich ore powder, 2.5% diamond-like carbon coating particles, 2% polyurethane, 0.5% modified calcium ion additive;

[0055] Premixing of basic components: Put 65% siliceous cement and 12% natural volcanic rock powder into a mixer in proportion and stir for 3 minutes to ensure the uniform distribution of basic components;

[0056] Addition and mixing of functional materials: Add 5% nano-silicate powder, 2.5% nano-iron oxide, 3% zinc-rich ore powder and 2.5% diamond-like carbon coating particles to the mixture and continue stirring for 5 - 8 minutes to completely disperse the nano-scale materials;

[0057] Incorporation of polymer and additive: Finally, add 2% polyurethane and 0.5% modified calcium ion additive and mix for 3 minutes to ensure the complete fusion of all components and obtain the final composite wear-resistant agent.

[0058] Example 3: Wear-resistant agent for high-durability airport dam concrete

[0059] Components and mass percentages: 70% siliceous cement; 10% natural volcanic rock powder; 3% nano-scale silicate powder; 4% nano-iron oxide (Fe3O4); 2% zinc-rich ore powder; 2% diamond-like carbon coating particles; 3% polyurethane (polyurea); 0.5% modified calcium ion additive.

[0060] Preparation steps:

[0061] Material preparation: Prepare the required raw materials: 70% siliceous cement, 10% natural volcanic rock powder, 3% nano-silicate powder, 4% nano-iron oxide, 2% zinc-rich ore powder, 2% diamond-like carbon coating particles, 3% polyurethane, 0.5% modified calcium ion additive;

[0062] Premixing of basic components: Add 70% siliceous cement and 10% natural volcanic rock powder into a mixer in proportion and stir for 2 minutes to ensure uniformity;

[0063] Addition and mixing of functional materials: Add 3% nano-silicate powder, 4% nano-iron oxide, 2% zinc-rich ore powder and 2% diamond-like carbon coating particles to the mixture in sequence and continue stirring for 6 minutes to ensure the complete dispersion of functional materials;

[0064] Incorporation of polymer and additive: Finally, add 3% polyurethane and 0.5% modified calcium ion additive and mix for 3 minutes to ensure the uniform fusion of all components and obtain the high-performance composite wear-resistant agent.

[0065] Example 1: High wear-resistant airport dam concrete wear-resistant agent

[0066] Comparative Example 1: Compared with Example 1, the difference is that the diamond-like carbon coating particles are removed, and the rest are the same.

[0067] Comparative Example 2: Compared with Example 1, the difference is that the addition of polyurethane is cancelled, and the rest are the same.

[0068] Comparative Example 1: Remove diamond-like carbon coating particles

[0069] Components and mass percentages:

[0070] Siliceous cement 60%; Natural volcanic rock powder 15%; Nano-scale silicate powder 4%; Nano iron oxide (Fe3O4) 3%; Zinc-rich ore powder 2.5%; Polyurethane (polyurea) 2.5%; Modified calcium ion additive 0.8%.

[0071] Comparative Example 2: Cancel the addition of polyurethane

[0072] Components and mass percentages:

[0073] Siliceous cement 60%; Natural volcanic rock powder 15%; Nano-scale silicate powder 4%; Nano iron oxide (Fe3O4) 3%; Zinc-rich ore powder 2.5%; Diamond-like carbon coating particles 3%; Modified calcium ion additive 0.8%.

[0074] Example 2: High erosion-resistant airport dam concrete wear-resistant agent

[0075] Comparative Example 3: Compared with Example 2, the difference is that the zinc-rich ore powder is removed, and the rest are the same.

[0076] Comparative Example 4: Compared with Example 2, the difference is that the diamond-like carbon coating particles are cancelled, and the rest are the same.

[0077] Comparative Example 1: Remove zinc-rich ore powder

[0078] Components and mass percentages:

[0079] Siliceous cement 65%; Natural volcanic rock powder 12%; Nano-scale silicate powder 5%; Nano iron oxide (Fe3O4) 2.5%; Diamond-like carbon coating particles 2.5%; Polyurethane (polyurea) 2%; Modified calcium ion additive 0.5%.

[0080] Comparative Example 2: Cancel diamond-like carbon coating particles

[0081] Components and mass percentages:

[0082] Siliceous cement 65%; natural volcanic rock powder 12%; nano-scale silicate powder 5%; nano iron oxide (Fe3O4) 2.5%; zinc-rich ore powder 3%; polyurethane (polyurea) 2%; modified calcium ion additive 0.5%.

[0083] Example 3: Wear-resistant agent for high-durability airport dam concrete

[0084] Comparative Example 5: Compared with Example 3, the difference lies in removing nano iron oxide, and the rest are the same.

[0085] Comparative Example 6: Compared with Example 3, the difference lies in canceling the modified calcium ion additive, and the rest are the same.

[0086] Comparative Example 1: Remove nano iron oxide

[0087] Components and mass percentages:

[0088] Siliceous cement 70%; natural volcanic rock powder 10%; nano-scale silicate powder 3%; zinc-rich ore powder 2%; diamond-like carbon coating particles 2%; polyurethane (polyurea) 3%; modified calcium ion additive 0.5%.

[0089] Comparative Example 2: Cancel the modified calcium ion additive

[0090] Components and mass percentages:

[0091] Siliceous cement 70%; natural volcanic rock powder 10%; nano-scale silicate powder 3%; nano iron oxide (Fe3O4) 4%; zinc-rich ore powder 2%; diamond-like carbon coating particles 2%; polyurethane (polyurea) 3%.

[0092] Experiment 1: Wear resistance and impact resistance test

[0093] Test objective: To evaluate the differences in wear resistance and impact resistance between Example 1 and Comparative Example 1 (removing diamond-like carbon coating particles) and Comparative Example 2 (canceling the addition of polyurethane).

[0094] Experimental steps:

[0095] Step 1: Wear resistance test

[0096] Sample preparation: Prepare wear-resistant samples of Example 1, Comparative Example 1, and Comparative Example 2. Each sample is cut into disks of the same size (diameter 50 mm, thickness 5 mm), and the surface is ensured to be flat.

[0097] Friction and wear test:

[0098] Use a friction and wear testing machine (e.g., Pin-on-Disk friction and wear machine) for testing. Install each sample on the testing machine.

[0099] Select specific load (such as 20 N), rotational speed (such as 500 rpm), test time (such as 60 min), and set the test temperature to 25 °C.

[0100] Measure the wear amount:

[0101] Measure the mass change of each sample after wear, and record the wear rate per minute.

[0102] Observe whether obvious cracks or spalling occur on the worn surface.

[0103] Step 2: Impact resistance test

[0104] Sample preparation: Prepare impact samples of Example 1, Comparative Example 1, and Comparative Example 2, with each sample size of 50 mm × 50 mm × 5 mm.

[0105] Impact test:

[0106] Use an impact testing machine (such as a drop hammer impact tester) for testing. Set different conditions such as impact energies of 10 J, 20 J, 30 J, etc.

[0107] Conduct multiple impact tests and observe the damage conditions of the samples under impacts of different energies.

[0108] Record the results:

[0109] Record the damage degree of the sample after each impact, the crack propagation situation, and mark the cracked area. Measure the length and width of the cracks to evaluate the impact resistance.

[0110] Table 1: Test results of wear resistance and impact resistance

[0111]

[0112]

[0113] Summary: When analyzing based on the test results of Experiment 1, we can summarize from multiple mechanistic perspectives. First, Example 1 is superior to Comparative Example 1 and Comparative Example 2 in terms of wear resistance and impact resistance, mainly due to the introduction of diamond-like carbon coating particles. The diamond-like carbon coating particles have extremely high hardness and anti-friction properties, which makes Example 1 show a lower wear rate in the friction and wear test. The diamond-like carbon coating particles can effectively disperse stress by filling the microcracks and voids in the cement matrix, thereby reducing surface damage and improving wear resistance. In Comparative Example 1, these particles are removed, resulting in the sample being more prone to cracks and damage in a high-impact and high-friction environment, so its wear resistance and impact resistance are relatively poor.

[0114] Secondly, the addition of polyurethane or polyurea played an important role in Example 1, which also helped to improve the impact resistance of the material. The addition of polyurethane made the wear-resistant agent have a certain flexibility, enabling it to absorb part of the energy when impacted and reducing the damage caused by brittle fracture. In contrast, the polyurethane in Comparative Example 2 was removed, resulting in the sample showing relatively fragile characteristics in the impact test. The lack of the high elasticity of polyurethane made the material more likely to generate cracks under impact, and the crack propagation speed was relatively fast, ultimately leading to breakage. Therefore, the presence of polyurethane played an indispensable role in improving the impact resistance.

[0115] Finally, the combination of friction and wear tests and impact tests revealed the complex performance of the material in practical applications. Although Example 1 showed relatively excellent results in terms of wear resistance and impact resistance, its performance improvement was not determined by a single material or a single property. The optimization of the overall mechanism was based on the composite effect of nanoscale materials (such as nano-silicate powder, nano-iron oxide, etc.) and polymers. Nano-materials not only provided higher surface activity and chemical stability but also enhanced the comprehensive performance of the material by improving the interfacial adhesion force. This multi-functional composite design not only improved the wear resistance of the material but also its cavitation resistance and impact resistance, making Example 1 have more excellent long-term performance in complex environments.

[0116] Experiment 2: Corrosion Resistance and Oxidation Resistance Tests

[0117] Test Objectives: To evaluate the differences in corrosion resistance and oxidation resistance between Example 2 and Comparative Example 3 (removing zinc-rich ore powder), and between Example 3 and Comparative Example 5 (removing nano-iron oxide).

[0118] Experimental Procedures:

[0119] Step 1: Corrosion Resistance Test

[0120] Sample Preparation: Prepare corrosion-resistant samples of Example 2 and Comparative Example 3. The size of each sample is 50mm×50mm×5mm, ensuring a flat surface.

[0121] Corrosion Environment Preparation:

[0122] Prepare a saline solution with a salt concentration of 5% (by weight) and adjust the temperature to 30°C.

[0123] Immerse the samples in the saline solution, ensuring that the samples are completely submerged.

[0124] Corrosion Test:

[0125] Immerse the samples in the salt water and take them out every 24 hours to observe the surface changes of the samples.

[0126] Record the mass loss, surface oxide layer change, and crack condition of the sample after each immersion.

[0127] Corrosion assessment:

[0128] Calculate the corrosion rate by measuring the mass change of the sample before and after immersion.

[0129] Observe the surface structure change after corrosion using a scanning electron microscope (SEM).

[0130] Step 2: Antioxidant performance test

[0131] Sample preparation:

[0132] Prepare the antioxidant samples of Example 3 and Comparative Example 5 with the same sample size as above.

[0133] Oxidation environment preparation: Expose the sample to a high-temperature oxidation environment with a set temperature of 600 °C and an oxygen concentration of 21%.

[0134] Oxidation test:

[0135] Take out the sample every 30 minutes, measure the mass change, and observe the formation of the surface oxide layer.

[0136] Record the color change of the sample, the thickness of the oxide layer, and the mass loss of the material.

[0137] Oxidation assessment:

[0138] Calculate the mass loss of the sample during the oxidation process and evaluate its antioxidant performance.

[0139] Use X-ray diffraction (XRD) to analyze the surface composition after oxidation and further evaluate the high-temperature oxidation resistance.

[0140] Table 2: Test results of corrosion resistance and antioxidant performance

[0141]

[0142]

[0143] Summary: Based on the test results of Experiment 2, first, the introduction of zinc-rich ore powder significantly improved the corrosion resistance in Example 2. Zinc has a good sacrificial anode effect and can provide a protective layer in the corrosion environment to prevent other components in the cement matrix from being corroded. After removing the zinc-rich ore powder in Comparative Example 3, the corrosion resistance decreased significantly, the mass loss of the sample increased, and the corrosion rate increased. This indicates that zinc-rich ore powder plays a key role in the corrosion resistance mechanism. It not only effectively reduces the direct contact between the brine solution and the matrix but also protects the material surface by forming a zinc oxide layer, making it more stable in acidic or corrosive environments.

[0144] Secondly, the introduction of nano iron oxide significantly enhanced the antioxidant performance of the material in Example 3. Nano iron oxide has a large specific surface area and strong adsorption capacity. It can form a stable iron oxide layer in a high-temperature oxidation environment, preventing oxygen from continuing to penetrate into the material interior, thereby improving the high-temperature resistance and antioxidant capacity of the material. After removing nano iron oxide in Comparative Example 5, the sample showed a higher mass loss and oxide layer thickness during oxidation, indicating that the lack of the protective effect of nano iron oxide led to deeper oxygen penetration and intensified oxidation reaction, further reducing the high-temperature stability of the material.

[0145] Finally, overall, the improved performance of Example 2 and Example 3 can be attributed to the synergistic interaction of each functional component in the composite material. In Example 2, the combination of zinc ore powder and cement matrix provided excellent corrosion protection, while in Example 3, nano iron oxide and other materials in the matrix jointly enhanced the high-temperature resistance and antioxidant performance. Compared with Comparative Example 3 and Comparative Example 5, the lack of these key components led to the performance deterioration of the material in the face of corrosion and oxidation environments. Therefore, the precise combination and reasonable use of different functional materials in the composite material significantly improved the comprehensive performance of corrosion resistance, oxidation resistance and high-temperature resistance.

[0146] Experiment 3: High-temperature resistance performance and stability test

[0147] Test objective: To evaluate the differences in high-temperature resistance performance and material stability between Example 3 and Comparative Example 6 (canceling the modified calcium ion additive).

[0148] Experimental steps:

[0149] Step 1: High-temperature resistance performance test

[0150] Sample preparation:

[0151] Prepare high-temperature resistant samples of Example 3 and Comparative Example 6 with dimensions of 50mm×50mm×5mm, ensuring the surface is flat.

[0152] High-temperature environment preparation:

[0153] Use a high-temperature furnace to expose the samples to a high-temperature environment of 600°C to test their high-temperature resistance performance.

[0154] Set the atmosphere to a conventional environment with an oxygen concentration of 21%, and maintain this temperature for a period of time (such as 90 min).

[0155] High-temperature resistance test:

[0156] At different time points (such as 30 min, 60 min, 90 min), take out the samples and record the mass change, color change and any surface damage of the samples.

[0157] Record the temperature change of the sample under high-temperature environment, as well as deformation, cracking and oxidation phenomena.

[0158] Evaluation and analysis:

[0159] Calculate the weight change at high temperature by measuring the mass loss of the sample.

[0160] Use a scanning electron microscope (SEM) to observe the oxide layer, crack propagation and structural changes.

[0161] Evaluate the thermal expansion resistance of the material and calculate the coefficient of thermal expansion through the dimensional change after temperature change.

[0162] Step 2: High-temperature stability analysis

[0163] Thermal cycle test:

[0164] Conduct multiple high-temperature cycles (such as 30 times, 500 °C - 600 °C) on the sample, with each cycle lasting 30 minutes, to test its thermal stability.

[0165] After each cycle, record the mass of the sample, the change of cracks and the surface damage condition.

[0166] Stability evaluation:

[0167] Evaluate its thermal stability by detecting the crack propagation degree and the mass loss of the sample.

[0168] Compare the deformation and structural damage conditions of the sample after different numbers of cycles to evaluate the high-temperature fatigue resistance of the material.

[0169] Table 3: Test results of high-temperature resistance performance and stability

[0170]

[0171]

[0172]

[0173] Summary: Based on the test results of Experiment 3, it can be analyzed from the mechanism perspective. First of all, the modified calcium ion additive plays a key role in improving the high-temperature resistance performance in Example 3. The calcium ion additive can react with other components in the cement matrix to form a stable calcium silicate structure, and these structures have good thermal stability under high-temperature environment. It can be seen from the experimental data that after the high-temperature test in Example 3, the crack propagation is small, the mass loss is low, and the formation of the oxide layer is relatively uniform. This indicates that the calcium ion additive helps to enhance the thermal stability of the cement matrix, enabling the material to maintain high mechanical properties and structural stability in high-temperature environment.

[0174] Secondly, Comparative Example 6 without the modified calcium ion additive showed poor stability in a high-temperature environment. Due to the lack of the promotion of the calcium ion additive, the cement matrix was prone to structural loosening and crack propagation at high temperatures, resulting in a decrease in the thermal expansion resistance of the material and ineffective dispersion of thermal stress. The experimental results showed that after multiple high-temperature cycles, Comparative Example 6 had a large mass loss, a thick oxide layer, and a fast crack propagation rate, indicating a lack of the protective effect of the calcium ion additive and a decrease in the crack resistance and oxidation resistance of the material in a high-temperature environment.

[0175] Finally, overall, the modified calcium ion additive in Example 3 collaborated with other functional materials (such as nano-scale mineral powders, etc.) to enhance the overall high-temperature stability of the material. The addition of the nano-scale material provided higher surface activity, which could effectively increase the bonding strength and thermal stability of the cement matrix, thereby reducing the damage caused by thermal expansion. In the high-temperature test, Example 3 showed good thermal expansion resistance and a low crack propagation rate, proving that the combined action of different functional components improved the comprehensive performance of the material. Compared with Comparative Example 6, Example 3 had stronger durability, less crack propagation, and a thinner oxide layer in a high-temperature environment.

[0176] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Special concrete wear-resistant agent for airport dam, characterized in that, By weight percentage, it includes the following components: Siliceous cement 50%-70%, with SiO2 content greater than 85%; Natural volcanic rock powder 10%-20%; Nanoscale silicate powder 3%-5%; Nano iron oxide 2%-4%; Zinc-rich ore powder 2%-3%; Diamond-like carbon coated particles 2%-4%; Polyurethane or polyurea, with dosage of 2%-3%; Modified calcium ion additive 0.5%-1%; Among them, the total dosage of the wear-resistant agent is 3%-20% based on the mass of the cementitious material.

2. The special concrete wear-resistant agent for airport dams according to claim 1, characterized in that, The specific surface area of the nano-scale silicate powder is 60,000 cm 2 / g, and the particle size range of the nano-scale silicate powder is 50 - 100 nm.

3. The special concrete wear-resistant agent for airport dams according to claim 1, characterized in that, The particle size range of the nano iron oxide is 30-50nm, and the nano iron oxide is Fe3O4 or its composite.

4. The special concrete wear-resistant agent for airport dams according to claim 1, characterized in that, The siliceous cement is selected from special cements with C2S content greater than 40% and C4AF content greater than 15%.

5. The special concrete wear-resistant agent for airport dams according to claim 1, characterized in that, The particle size range of the natural volcanic rock powder is 50-200μm, the particle size range of the zinc-rich ore powder is 50-100μm, and the particle size range of the diamond-like carbon coated particles is 50-100μm.

6. The special concrete wear-resistant agent for airport dams according to claim 1, characterized in that The modified calcium ion additive is selected from calcium aluminate cement, calcium nitrate or calcium chloride.

7. The preparation method of the special concrete wear-resistant agent for airport dams according to any one of claims 1-6, characterized in that, It includes the following steps: S1. Material preparation: Prepare siliceous cement, natural volcanic rock powder, nanoscale silicate powder, nano iron oxide, zinc-rich ore powder, diamond-like carbon coated particles, polyurethane or polyurea, and modified calcium ion additive; S2. Premixing of basic components: Put the siliceous cement and natural volcanic rock powder into the mixing equipment according to the designed ratio, and stir for 2-3 minutes to form a uniform basic mixing system; S3. Addition and mixing of functional materials: Sequentially add nanoscale silicate powder, nano iron oxide, zinc-rich ore powder and diamond-like carbon coated particles to the basic component mixture, and continue to stir for 5-8 minutes to make the functional nanomaterials evenly dispersed and fully contact with the basic powder materials; S4. Incorporation of polymer and additive: Add polyurethane or polyurea polymer material and modified calcium ion additive to the above mixing system, and mix again for 3-5 minutes to make all components evenly fused to form a high-performance composite wear-resistant agent.

8. Use of the special concrete wear-resistant agent for airport dams according to any one of claims 1-6, characterized in that, This wear-resistant agent is applied to airport dam concrete or mortar projects with relatively serious impact abrasion and cavitation erosion to improve the impact abrasion strength and cavitation resistance of the concrete. The applicable concrete strength grade for the project is C60 to C80.

9. The application of the special concrete wear-resistant agent for airport dams according to claim 8, characterized in that, Add the wear-resistant agent, cement, fly ash or sand to the concrete mixer in dry powder form at the same time, or add it to the dry materials. It is strictly prohibited to stir with water alone or measure by volume method. The feeding order is: small stones, sand, cement, fly ash and wear-resistant agent, and finally add water. The mixing time is 90 seconds longer than that of ordinary concrete or the total mixing time is not less than 180 seconds. If it is necessary to shorten the mixing time, it should be confirmed through a mixing uniformity test.

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